U.S. Prisons Allow Extremism to Fester, Study Warns

Heather Coffman was among the first U.S. prisoners to return to her hometown, in Virginia, after serving time on charges related to support for Islamic State.

“I’m home,” she wrote on her Facebook page in December. Next, she posted a series of images and messages, some labeled as Islamic State material, imploring all Muslim women to cover up with the most conservative style of thick, loose-fitting clothes. After more than four years in prison, Ms. Coffman’s rigid views had scarcely moderated.